I purchased this used from a guy at work for $50, knowing absolutely nothing about it but knowing that for $50 just about any kind of pro equipment is a steal. (As long as it works! :) ) This drum machine is rad. It has an internal speaker system and battery sockets so it is fully portable. The interface is kind of funky; you use a sort of shift-and-hold-button-technique to move around through the drum machine's "OS". You can only quantize down to 1/16th notes also, which is a bit annoying. The SOUNDS tho... I cannot find ANYTHING about this drum machine on the internet.. is it rare, or does everyone think it sucks too much to be mentioned? Let me tell ya, I love my RY-10. The sounds on it rule! I think it must have been one of Yamaha's first 16 bit drum machines, so the samples are a bit on the noisy side, which makes them rock. All the sound fx (there are 40 of them) sound like they came sampled from Atari 2600 games. This thing also has fifteen BASS sounds to choose from. Now, these bass sounds are not great by any means, but I have found them to be usable. If you can find this thing for $100 or less, GRAB IT. You will not be sorry. It's fun as hell and sounds great.